Download By Dr. Dick Dekker, Ph.D. - Alberta Wilderness Association

Will Alberta’s Black Wolves Benefit
from Climate Change?
By Dr. Dick Dekker, Ph.D.
A team of 15 geneticists and biologists
has recently written that the black fur of
wolves is “a gift from the dogs” and that
it gives them a camouflage advantage
over their grey cousins as the tree line
advances onto the tundra zone due to
climate change.
B
Features
WLA December 2009 • Vol. 17, No. 6
14
ased on the analysis of
mitochondrial DNA, the black fur
in western wolves is said to have
been caused by a mutation that was lost
to the species in ancient times but was
subsequently re-acquired after wolves
hybridized with domestic dogs. And this
was most likely to have happened, the
scientists speculated, about 15,000 years
ago after some wolves crossed over from
Asia into Alaska via the land bridge that
developed between the two continents
during the Pleistocene ice age.
Be that as it may, in my opinion, the
scientists exaggerated the significance of
their finding by claiming that black wolves
have an evolutionary edge over their grey
cousins that makes them better adapted
to climate change and the expected
northward expansion of the boreal forest.
Black fur, the scientists thought, is an
asset to a forest-dwelling predator.
This premise is fanciful because the
effects of global warming may vary in
different landscapes. As predicted by
climatologists, rising annual temperatures
could lead to the demise of Alberta’s
forests and create more open and
snow-free ground. There, the so-called
camouflage advantage for a black animal
would be lost and in fact become a
disadvantage. Furthermore, in my 40
years of field observations in Jasper
National Park, black wolves are at all
times more visible than grey ones, even
among the trees.
The taxonomic origin of wolves
is complicated and was vigorously
debated at the Second North American
Symposium on Wolves held at the
University of Alberta in August of 1992.
Based on the fossil record, Professor
Black fur in wolves is unknown in Eurasia and very rare in eastern North America, but
common from Alaska down to Yellowstone. At about 70 percent of the local population,
the black variant is most numerous in Jasper National Park, which makes the common
name Gray Wolf actually a misnomer. This impressive pair was photographed on the
eastern boundary of Jasper. With advancing age, black wolves may turn silvery grey
or even white. PHOTO: B. GENEREUX
Ronald Nowak argued that the forbearer
of all wolves is the Red Wolf of the
American southeast. Long ago, the
ancestors of these New World wolves
crossed over into Asia and Europe. There,
they grew to the large size of the presentday Gray Wolf and much later returned
to North America, where some acquired
a black coat. In western wolves, from
Alaska down to Yellowstone, the black
percentage varies from 30 to 50 percent.
It is highest in Jasper National Park. Of
the circa 800 wolves I have seen there,
just over 70% were black.
Melanism is caused by excessive
production of black pigment in fur or
skin, but it is not confined to the Gray
Wolf. It also occurs in the Red Fox,
where it can have nothing to do with
hybridization with dogs because foxes
and dogs have different chromosome
numbers, which prevents interbreeding.
Melanism is also evident in the Grey
Squirrel. After this eastern tree-hugger
was introduced near Vancouver, spotting
a black squirrel has become common for
visitors to Stanley Park.
Black fur has even been reported
in the Richardson’s Ground Squirrel or
gopher. Colonies of black gophers have
been seen in fields near Tofield and west
of Edmonton, as well as in the Yukon and
Jasper National Park.
The discovery that western wolves
acquired their black gene through contact
with domesticated dogs is interesting, but
why present it in the context of climate
change? Or has climate change become
the buzzword in wildlife research?
Dick Dekker, a naturalist born in
Holland, came to Canada in 1959 to find
wilderness. He has written ten books as
well as numerous articles and research
papers. Since 1960 he has been an
outspoken defender of wolves and habitat
conservation.